Along with advancement of distribution and complexity of information systems, increase of the system operation management cost has become a problem. Therefore, an operation management system in which a management system collects and stores pieces of resource information about various resources such as calculators and network devices, and operation and control of the system is carried out based on the stored pieces of resource information is provided.
For example, the management system collects the pieces of resource information from management target systems such as network systems and Web systems, stores the pieces of information, and compares the resource information with performance deterioration conditions. Thus, an example of the operation management system in which the management system automatically detects performance deterioration phenomena of the management target systems is disclosed in Patent Literature 1.
Generally, in an information system, the resource information owned by the management target systems is always updated. Therefore, the management system has to keep collecting the resource information owned by the management target systems. This is for the reason that, when the management system uses old resource information, the system is operated or controlled based on wrong judgement.
Therefore, in the system disclosed in Patent Literature 1 and in many other operation management systems, the management system collects the pieces of resource information, which is owned by the management target systems, at intervals periodically specified in advance.
Moreover, for example, a management system groups resource information for each type of management target systems, and update intervals and concurrent update numbers are set for the resource information groups. Then, the management system generates a collection schedule, which satisfies the update intervals under the restriction of the concurrent update number, for each resource information group. In accordance with the generated collection schedule, the management system collects pieces of resource information and updates a cache. Then, in accordance with a search request, the management system searches the cache and provides the corresponding resource information to a search request source. This operation management system is disclosed in Patent Literature 2.
On the other hand, a MDS (Monitoring Discovery System) is disclosed in Non-Patent Literature 1 as an operation management system of a wide-area distributed system. In the MDS, resource information is managed by directories. When a search process for searching the resource information is executed, the management system acquires the resource information and stores it in a cache. Then, when the resource information stored in the cache and the resource information required by the search request source is the same, the management system provides the resource information stored in the cache to the request source. Thus, the time of searching the resource information is shortened. Time of validity of the cache is set in advance for the resource information collected by the MDS. Therefore, when the search request source requests the resource information of which time of validity has been expired, the management system discards the resource information stored in the cache and executes a process of acquiring latest resource information. The MDS can be subjected to hierarchical cooperation of a plurality of MDSs, and they are utilized in systems of various modes including a single cluster to a large scale distribution system.    Patent Literature 1: Unexamined Japanese Patent Application KOKAI Publication No. 2004-145536    Patent Literature 2: International Publication WO2006/046486A1    Non-Patent Literature 1: Grid information services for distributed resource sharing Czajkowski, K.; Fitzgerald, S.; Foster, I.; Kesselman, C.; High Performance Distributed Computing, 2001. Proceedings, 10th IEEE International Symposium on, 7-9 Aug. 2001